Real can move eight points clear of second placed Barcelona tonight, if they can take all three points off La Liga strugglers, Villarreal, at El Madrigal.
"We have an advantage [over Barça] which means a lot and does not mean that much at the same time," Kaká told AS.
"We know that Barça are very strong and that they have great players, so we will have to be very alert until we have mathematically won the title."
